1. Technical Field
The present invention relates to a fabricated food product made in significant part from fresh potato mash. More specifically, this invention relates to making dough that has improved strength and produces dehydrated and/or fried product with a light texture having improved, more natural flavor. Particular formulations are well-suited for creating fabricated, extruded snack products.
2. Description of Related Art
In the food industry, potato-based products are normally made from dough mixes incorporating potato derivatives such as potato flakes, potato flour, potato granules, and/or potato starch. Potato-based products made in such fashion can deliver numerous shapes and attributes, but unfortunately most of the potato flavor is lost in the process of producing the ingredients. In general, potato dough made from potato derivative products tends to be weak and does not maintain adequate strength for sheeting or extruding when formed into shapes. Although prior art methods have shown that sheetable potato doughs could be made from raw potato stock, those potatoes underwent several dehydration stages to reduce the moisture content of the raw potatoes.
For example, U.S. Pat. No. 6,251,465 granted to Bello et al. discloses methods for making improved potato products by using raw potato stock as a starting material to form a sheetable dough. This patent discloses methods to produce a potato gel suitable for sheeting or extruding. This patent discloses a controlled dehydration method at about 195 degrees C. until the moisture content of potato pieces reaches 40% to 60%. Although Bello teaches that sheetable potato dough can be made, at least in part, from raw potato stock, the Bello method requires several separate dehydration and cooling stages, each causing more and more loss of natural flavor. Several other notable points from Bello are as follows: the Bello potato gel is partially gelatinized and not fully gelatinized before it is mixed with dry ingredients, as seen in the dramatic increases in viscosity as temperature is increased in Bello FIGS. 2 through 4; Bello's high-shear grinding is more likely to damage potato starch molecules; moisture is lost during baking as practiced in Bello; product is chilled between 30° C. (86° F.) and 50° C. (122° F.); some flavor volatiles are lost during dehydration; Bello requires partial dehydration of chip stock potato to no greater than about 60% moisture content for use in its process; and Bello teaches that a suitable dough formulation contains potato granules, wheat starch, and corn syrup solids. Thus, a need exists for an improved, gentler method for removing moisture from fresh potatoes and for processing at much lower, controlled cooking temperatures to create fabricated potato products from fresh potatoes.
Past attempts to make potato dough and snacks from fresh potato mash have failed due to high moisture content of the fresh mash. Fresh potatoes are infrequently used for such dough, especially in the case of extruded snack pieces. Several patents disclose improvements to potato-based dough and/or mash including dough and/or mash composition, mixing, and preparation of potatoes as ingredients.
U.S. Pat. No. 4,169,166 issued on Sep. 25, 1979 to Kiett et al, discloses an extruding process to remove the skins, eyes and defects of potatoes. Potato pulp is extruded as cooked potato pieces are conveyed by a compression-type screw conveyor along the length of a perforated conduit. Less cellular damage occurs to the potato pulp as compared to some prior art methods. The pulp has a stronger than the usual flavor of mashed potatoes. However, the extruding process generally is coarse and there are other, less damaging methods of reducing potato pulp to small pieces.
U.S. Pat. No. 6,808,734 issued on Oct. 26, 2004 to Villagran, discloses a dough composition of potato flour between 35% and 85% by weight where the dough has a soluble Amylose to soluble Amylopectin ratio of from about 0.4 to about 4. Such amounts of Amylose and Amylopectin account for an improved crispness to a finished chip product. However, there is no discussion of the use of fresh potatoes in the dough formulation.
Relatively little in the prior art discloses the use of a relatively large quantity of fresh potatoes to form a potato dough suitable for forming snack pieces or sheeting. This was so because fresh potato mash prepared by prior art methods had very high moisture content, typically from about 75% to about 85%. In the prior art, use of relatively large quantities of fresh potatoes introduced problems with texture and stripping of flavor from the fresh potatoes in the dehydration process.
Potato dough requires less than about 50% moisture for potato pre-forms to retain their shape during processing and dehydration to a finished snack of a light texture. This limits the amount of fresh potato mash that can be used in a dough system. Further, potato mash is traditionally cooked at near the boiling point of water (212 degrees F.). However, such cooking removes or denatures desirable flavor chemical components.
U.S. Pat. No. 3,634,105, granted on Jan. 11, 1972 to Beck, describes “a process for producing large potato pieces which can be rehydrated and prepared as pan fried potatoes or hash brown potatoes . . . . ” Beck teaches that raw potatoes can be first cooked and then comminuted to form a potato slurry or mash. The Beck patent teaches that when “the heat treatment step to gelatinize the raw starch is accomplished before the dough is extruded,” the “heat-treated dough mix must be kept hot until extrusion is completed. The reference further teaches that “effective starch gel formation in the dough requires a minimum heat treatment temperature of about 190[deg] F. In tests where dough was heated to only 170[deg] F., no beneficial result was found.” Beck also states that “if the dough cools before the finish of mixing or before extrusion, the gel structure is disrupted and the advantages of our process are decreased.” As previously noted, however, such cooking at relatively high temperatures removes or denatures desirable flavor chemical components. It is therefore desirable to have a method of forming and cooking potato dough at lower temperatures so that more of the desirable flavor components are retained.
Similarly, U.S. Pat. No. 4,109,012, granted to Bates on Aug. 22, 1978, teaches that relatively high-temperature cooking is necessary to cook fresh potato in a process for making coherent, workable potato dough. For example, Bates teaches that “whole potatoes are then cooked by baking until they are completely cooked . . . . Also, for the purposes of this invention, ‘complete’ cooking is hereby defined as that stage in cooking when the internal temperature of the center of the potato has reached a temperature of at least about 190[deg] F.”
U.S. Pat. No. 4,005,139, granted to Kortschot on Jan. 25, 1977, is yet another reference that discloses a method of forming potato dough from a slurry or mash of potatoes. Kortschot, however, teaches that dehydrated potato solids and water can be rapidly and severely mixed and agitated to form a potato slurry, which can then be fed to an extruder to produce a product capable of being fried.
Thus, a need exists for a formulation and method for producing a potato dough or masa wherein fresh potatoes are maximized by weight of the ingredients. A need exists to provide ingredients that maintain natural potato flavors while retaining a light texture as a snack. A need exists to gently handle and process raw potatoes to provide for desired characteristics in finished products, particularly those that are extruded and fried. A need exists to remove water from fresh potato pulp so that a higher relative amount of fresh potato can be added to a dough formulation. A need exists to keep processing temperatures as low as possible to minimize the degradation and loss of flavor constituents. A need exists for a method of producing shaped collets that resist deformation in subsequent dehydration and/or frying processes while retaining a light texture in the finished product.